build: use the exported config for libdispatch
build: use the exported config for libdispatch

Pass along the configuration through the exported target for the standard
library.  Still pass the compiler by hand to allow building libdispatch against
just a build of the standard library.

CodaFi/swift,practicalswift/swift,glessard/swift,alblue/swift,gribozavr/swift,glessard/swift,allevato/swift,CodaFi/swift,airspeedswift/swift,sschiau/swift,brentdax/swift,danielmartin/swift,CodaFi/swift,amraboelela/swift,danielmartin/swift,airspeedswift/swift,xwu/swift,xwu/swift,tkremenek/swift,practicalswift/swift,karwa/swift,brentdax/swift,austinzheng/swift,gregomni/swift,xedin/swift,glessard/swift,parkera/swift,jckarter/swift,xwu/swift,gregomni/swift,ahoppen/swift,shajrawi/swift,JGiola/swift,karwa/swift,aschwaighofer/swift,xwu/swift,devincoughlin/swift,atrick/swift,amraboelela/swift,shajrawi/swift,amraboelela/swift,shajrawi/swift,harlanhaskins/swift,atrick/swift,jckarter/swift,rudkx/swift,jckarter/swift,roambotics/swift,aschwaighofer/swift,parkera/swift,xedin/swift,allevato/swift,karwa/swift,JGiola/swift,xwu/swift,hooman/swift,gregomni/swift,xwu/swift,benlangmuir/swift,ahoppen/swift,brentdax/swift,xwu/swift,jckarter/swift,atrick/swift,parkera/swift,rudkx/swift,nathawes/swift,shajrawi/swift,rudkx/swift,apple/swift,ahoppen/swift,shahmishal/swift,jmgc/swift,practicalswift/swift,nathawes/swift,apple/swift,airspeedswift/swift,tkremenek/swift,lorentey/swift,shajrawi/swift,allevato/swift,amraboelela/swift,harlanhaskins/swift,karwa/swift,sschiau/swift,karwa/swift,parkera/swift,jmgc/swift,sschiau/swift,jckarter/swift,tkremenek/swift,roambotics/swift,roambotics/swift,brentdax/swift,aschwaighofer/swift,brentdax/swift,shahmishal/swift,lorentey/swift,gribozavr/swift,shahmishal/swift,atrick/swift,roambotics/swift,hooman/swift,hooman/swift,lorentey/swift,lorentey/swift,hooman/swift,gribozavr/swift,gribozavr/swift,JGiola/swift,JGiola/swift,devincoughlin/swift,devincoughlin/swift,rudkx/swift,danielmartin/swift,devincoughlin/swift,tkremenek/swift,alblue/swift,gribozavr/swift,alblue/swift,benlangmuir/swift,xedin/swift,CodaFi/swift,amraboelela/swift,allevato/swift,roambotics/swift,shahmishal/swift,gribozavr/swift,harlanhaskins/swift,tkremenek/swift,roambotics/swift,ahoppen/swift,lorentey/swift,harlanhaskins/swift,brentdax/swift,karwa/swift,nathawes/swift,glessard/swift,airspeedswift/swift,sschiau/swift,lorentey/swift,alblue/swift,practicalswift/swift,karwa/swift,jmgc/swift,danielmartin/swift,jmgc/swift,allevato/swift,sschiau/swift,gribozavr/swift,jmgc/swift,devincoughlin/swift,aschwaighofer/swift,parkera/swift,stephentyrone/swift,xedin/swift,xedin/swift,amraboelela/swift,stephentyrone/swift,hooman/swift,nathawes/swift,sschiau/swift,alblue/swift,glessard/swift,austinzheng/swift,austinzheng/swift,jmgc/swift,parkera/swift,jmgc/swift,jckarter/swift,amraboelela/swift,ahoppen/swift,rudkx/swift,benlangmuir/swift,austinzheng/swift,JGiola/swift,JGiola/swift,ahoppen/swift,karwa/swift,apple/swift,austinzheng/swift,lorentey/swift,CodaFi/swift,practicalswift/swift,airspeedswift/swift,hooman/swift,lorentey/swift,harlanhaskins/swift,shahmishal/swift,practicalswift/swift,xedin/swift,danielmartin/swift,apple/swift,parkera/swift,stephentyrone/swift,aschwaighofer/swift,sschiau/swift,shajrawi/swift,gregomni/swift,xedin/swift,tkremenek/swift,brentdax/swift,atrick/swift,sschiau/swift,xedin/swift,glessard/swift,nathawes/swift,tkremenek/swift,nathawes/swift,shahmishal/swift,hooman/swift,allevato/swift,stephentyrone/swift,gribozavr/swift,CodaFi/swift,gregomni/swift,CodaFi/swift,allevato/swift,alblue/swift,shajrawi/swift,shahmishal/swift,stephentyrone/swift,parkera/swift,practicalswift/swift,danielmartin/swift,shajrawi/swift,rudkx/swift,stephentyrone/swift,apple/swift,danielmartin/swift,gregomni/swift,jckarter/swift,airspeedswift/swift,harlanhaskins/swift,devincoughlin/swift,nathawes/swift,atrick/swift,devincoughlin/swift,aschwaighofer/swift,apple/swift,harlanhaskins/swift,alblue/swift,austinzheng/swift,practicalswift/swift,airspeedswift/swift,aschwaighofer/swift,shahmishal/swift,benlangmuir/swift,devincoughlin/swift,stephentyrone/swift,benlangmuir/swift,benlangmuir/swift,austinzheng/swift